1. Field of the Invention
This invention relates to the preparation of low molecular weight olefinic hydrocarbons from mixtures of carbon monoxide and hydrogen using a heterogeneous perovskite catalyst in a modified Fisher-Tropsch process.
2. Background
Commonly assigned U.S. Pat. No. 4,151,123 discloses catalysts which are useful for the oxidation of hydrocarbons and carbon monoxide and for the reduction of nitric oxide. The catalysts comprise an oxide of a transition metal having an atomic number of 23 to 30, 42 to 57 or 74 to 79 deposited on a second metal oxide having a perovskite structure.
U.S. Pat. No. 4,171,320 discloses catalysts which are useful for the preparation of hydrocarbons, with reduced methane formation, and for the selective production of olefinic hydrocarbons, preferably C.sub.2-5 olefins. The feed comprises a carbon monoxide/hydrogen synthesis gas stream and the catalyst comprises ruthenium on a support comprising at least one refractory Group V-B metal oxide, preferably V.sub.2 O.sub.3, Nb.sub.2 O.sub.5 or Ta.sub.2 O.sub.5.
U.S. Pat. No. 4,199,522 discloses an improved Fischer-Tropsch process for the preparation of olefinic hydrocarbons having two to four carbon atoms. The improvement comprises using a catalyst having a surface area less than about 100 m.sup.2 /g and consisting essentially of:
(1) at least one material selected from the group consisting of the sulfide, oxide or metal of Mo, W, Re, Ru, Ni, Pd, Rh, Os, Ir and Pt; PA1 (2) at least one material selected from the group consisting of the hydroxide, oxide or salt of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba and Th; and PA1 (3) optionally, a support.
It is an object of this invention to provide a modified Fischer-Tropsch process for the production of low molecular weight olefinic hydrocarbons from carbon monoxide/hydrogen synthesis gas. Another object is to provide a perovskite catalyst which is useful in such a process. Still another object is to provide such a catalyst, for use in such a process, to produce low molecular weight olefinic hydrocarbons, in preference to their saturated analogs. These and other objects will become apparent hereinafter.